Pedicle screw removal tool and method of use

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No. 15/344,152, filed on Nov. 4, 2016, now U.S. Pat. No. 10,820,936. Each patent application identified above is incorporated here by reference in its entirety to provide continuity of disclosure.

FIELD OF THE INVENTION

The present disclosure relates to tools for use during spinal surgery. In particular, the present disclosure relates to a pedicle screw removal tool.

BACKGROUND OF THE INVENTION

Spinal fusion, also called spondylodesis or spondylosyndesis, is a neurosurgical surgical technique that joins two or more vertebrae. Supplementary bone tissue or artificial bone is used to augment natural bone growth processes to fuse two or more adjoining vertebrae. When additional stability is required, vertebrae can be stabilized with screws through the pedicles of each vertebrae and connected with a stability rod.

<figref idref="DRAWINGS">FIG. <b>1</b></figref> shows four pedicle screws <b>102</b>, <b>104</b>, <b>106</b>, and <b>108</b> anchored in the pedicles of two adjoining vertebrae <b>110</b> and <b>112</b>. Stability rod <b>114</b> is anchored by pedicle screws <b>102</b> and <b>106</b>. Stability rod <b>116</b> is anchored by pedicle screws <b>104</b> and <b>108</b>.

A pedicle screw is a particular type of bone screw designed for implantation during a spinal fusion procedure. A common type of pedicle screw is a “tuliped” pedicle screw that is comprised of a “U” shaped body affixed to a threaded section. The “U” shaped body presents a channel for seating the rod. A threaded end cap engages the body to secure the rod to the screw. The body includes a machined recess shaped for receiving a screwdriver type tool which is used to implant and remove the pedicle screw.

Referring to <figref idref="DRAWINGS">FIGS. <b>2</b>A and <b>2</b>B</figref>, the components of a common tuliped pedicle screw are shown. Pedicle screw <b>200</b> comprises threaded section <b>202</b> connected to body <b>204</b>. Threaded section <b>202</b> has longitudinal axis <b>226</b>. Body <b>204</b> forms channel <b>206</b> between blades <b>208</b> and <b>210</b>. Body <b>204</b> includes opening <b>212</b> opposite threaded section <b>202</b>. Opening <b>212</b> leads to channel <b>206</b>. At the base of the channel, the tuliped pedicle screw includes socket <b>230</b> used to install the screw into bone. Internal thread <b>214</b> is formed on each blade <b>208</b> and <b>210</b> proximate opening <b>212</b>. End cap <b>216</b> is disc shaped and includes exterior thread <b>218</b> sized to engage internal thread <b>214</b>. End cap <b>216</b> further defines socket <b>220</b> shaped to receive a screwdriver type tool. Rod <b>222</b> fits within in channel <b>206</b>. End cap <b>216</b> is threadably engaged with body <b>204</b> and secures rod <b>222</b> to pedicle screw <b>200</b>.

Occasionally it is necessary to remove the pedicle screws after successful spinal fusion and stability are achieved. During surgery, a universal removal tray is utilized. The tray is equipped with many tools necessary to accommodate the different sizes and shapes of pedicle screws. Removal can be difficult because often the screws have become incarcerated in the bone and will not turn easily. Further, the body socket is many times filled with boney growth. The boney growth makes insertion of a removal tool difficult. As a result, the channel and the body socket is often stripped, bent, or broken during the removal procedure.

Several techniques have been developed to effect removal of a pedicle screw once its integrity is compromised. For example, one technique involves bisecting the stability rod, and securing it to the screw with an end cap. Pliers are then used to hold the rod and apply torque to the screw. This method creates a problem because ends of the rod can cause damage to the surrounding tissue leading to substantial bleeding and prolonged recovery time. As a second example, a cutting wheel may be used to notch the top of the screw in order to facilitate the use of a bladed removal tool. A problem with this approach is that metal shavings resulting from the procedure resist removal through irrigation and can contaminate the surrounding tissue. A more serious problem is that the cutting wheel, if not used carefully, may damage the spinal cord causing paralysis.

Hence, there is a need for a pedicle screw removal device that can be universally used for all sizes and shapes of tuliped pedicle screws that will function to cleanly remove a compromised screw without risk of contamination or damage to surrounding tissues.

SUMMARY OF THE INVENTION

A preferred embodiment is comprised of a tapered shaft having a right angle removal tip formed as its distal end and a generally square head on the proximal end. The removal tip is integrally formed with a tapered section which expands the overall circumference of the shaft. The tapered section leads to a cylindrically shaped handle section. The handle section may include a set of serrations. The removal tip is sized to match a stability rod and to easily engage the channel of a tuliped pedicle screw. The square head is designed to accommodate a ratchet or “T” handle.

In an alternate embodiment, the removal tip includes opposing prongs.

In another alternate embodiment, the handle section includes opposing members extending from the shaft to form a “T” shaped handle. Any combination of the alternate embodiments of the tip and handle is envisioned.

In use, the removal tip is inserted into the channel of a tuliped pedicle screw and secured to the screw with an end cap. The shaft is rotated via the handle section or with a torque producing tool attached to the head. The shaft is rotated along its longitudinal axis in a rotational direction that unscrews the pedicle screw from the bone. The removal tip eliminates the need for removal of boney tissue from the body socket or, alternatively, is useful after the body socket is compromised during removal.

Those skilled in the art will appreciate the above-mentioned features and advantages of the disclosure together with other important aspects upon reading the detailed description that follows in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

<figref idref="DRAWINGS">FIG. <b>1</b></figref> is an isometric view of vertebrae anchored by pedicle screws and stability rods as known in the prior art.

<figref idref="DRAWINGS">FIG. <b>2</b>A</figref> is an isometric view of a tuliped pedicle screw as known in the prior art.

<figref idref="DRAWINGS">FIG. <b>2</b>B</figref> is an exploded isometric view of a tuliped pedicle screw engaged with a stability rod as known in the prior art.

<figref idref="DRAWINGS">FIG. <b>3</b>A</figref> is an isometric view of a preferred embodiment.

<figref idref="DRAWINGS">FIG. <b>3</b>B</figref> is a side view of the preferred embodiment of <figref idref="DRAWINGS">FIG. <b>3</b>A</figref>.

<figref idref="DRAWINGS">FIG. <b>4</b>A</figref> is an isometric view of the preferred embodiment of <figref idref="DRAWINGS">FIG. <b>3</b>A</figref> positioned so that the longitudinal axis of the screw is coplanar with the longitudinal axis of the tool.

<figref idref="DRAWINGS">FIG. <b>4</b>B</figref> is an isometric view of the preferred embodiment of <figref idref="DRAWINGS">FIG. <b>3</b>A</figref> engaged with a tuliped pedicle screw.

<figref idref="DRAWINGS">FIG. <b>4</b>C</figref> is a flowchart of a preferred method of using the tool.

<figref idref="DRAWINGS">FIG. <b>5</b></figref> is a side view of an alternate preferred embodiment.

<figref idref="DRAWINGS">FIG. <b>6</b></figref> is a side view of an alternate preferred embodiment.

<figref idref="DRAWINGS">FIG. <b>7</b></figref> is a side view of an alternate preferred embodiment.

<figref idref="DRAWINGS">FIG. <b>8</b></figref> is a side view of an alternate preferred embodiment.

<figref idref="DRAWINGS">FIG. <b>9</b></figref> is a side view of an alternate preferred embodiment.

DETAILED DESCRIPTION OF THE INVENTION

In the description that follows, like parts are marked throughout the specification and figures with the same numerals, respectively. The figures are not necessarily drawn to scale and may be shown in exaggerated or generalized form in the interest of clarity and conciseness.

Referring to <figref idref="DRAWINGS">FIGS. <b>3</b>A and <b>3</b>B</figref>, pedicle screw removal tool <b>300</b> is a generally tapered cylindrical shaft comprising lower section <b>302</b> integrally formed with neck <b>304</b>. Neck <b>304</b> is integrally formed with handle <b>306</b>. Tip <b>308</b> is integrally formed with lower section <b>302</b> opposite neck <b>304</b>. Head <b>310</b> is integrally formed with handle <b>306</b> opposite neck <b>304</b>. Torque imposing tool <b>313</b> is removably attached to the head. The torque imposing tool may be, for example, a ratchet adaptor which applies torque in only one rotational direction. In another example, the torque imposing tool can be a simple crescent wrench. In yet another example, the torque imposing tool can be a torque wrench indicating the amount of torque applied to prevent shearing of the pedicle screw shaft. Lower section <b>302</b> is axially aligned with neck <b>304</b>. Neck <b>304</b> is axially aligned with handle <b>306</b>. Handle <b>306</b> is axially aligned with head <b>310</b>. Lower section <b>302</b>, neck <b>304</b>, handle <b>306</b>, and head <b>310</b> all share central longitudinal axis <b>312</b>. Tip <b>308</b> is generally “L” shaped formed by prong <b>314</b>. Prong <b>314</b> extends from tip <b>308</b> generally perpendicular to lower section <b>302</b>. In a preferred embodiment, pedicle screw removal tool <b>300</b> is constructed of surgical grade stainless steel.

The overall length of pedicle screw removal tool <b>300</b> can range from approximately eight to twelve inches depending on desired use. Prong <b>314</b> generally ranges from ⅛ to ½ inch in diameter. All dimensions are provided with a ±5% tolerance. The length of prong <b>314</b> ranges from approximately ½ to one inch. Lower section <b>302</b> ranges in length from approximately three to five inches. Lower section <b>302</b> generally ranges from ⅛ to ½ inch in diameter. The length of neck <b>304</b> ranges from approximately one to two inches. Neck <b>304</b> is a generally frustoconical shape with an increasing diameter from a range of ⅛ to ½ inch in diameter at the connection of neck <b>304</b> to lower section <b>302</b> to a range of ½ inch to ¾ inch in diameter at the connection of neck <b>304</b> to handle <b>306</b>. Handle <b>306</b> ranges in length from approximately three to four inches. Handle <b>306</b> generally ranges from ½ to ¾ inch in diameter. In an alternate embodiment, handle <b>306</b> may include serrations <b>316</b>. Head <b>310</b> ranges in length from approximately ½ to one inch. Head <b>310</b> has a generally square cross-section width a width that ranges from approximately ⅛ to ¾ of an inch. In alternate embodiments, head <b>310</b> may have other polygonal cross-sectional shapes suitable for attachment of the torque imposing tool.

Referring to <figref idref="DRAWINGS">FIGS. <b>4</b>A and <b>4</b>B</figref>, a method of using pedicle screw removal tool <b>300</b> to remove a tuliped pedicle screw will be further described.

At step <b>450</b>, residual tissue is cleared from the end cap from the pedicle screw. At step <b>452</b>, end cap <b>216</b> is removed using the appropriate spanner, if possible. In cases of advanced bone growth, the cap may remain in place in the screw. However, preferably the cap is at least loosed sufficiently to dislodge and remove the stability rod. At step <b>454</b>, stability rod <b>222</b> is removed. At step <b>456</b>, remaining tissue surrounding body <b>204</b> of pedicle screw <b>200</b> is then removed. At step <b>458</b>, tip <b>308</b> is inserted into channel <b>206</b> such that prong <b>314</b> is adjacent blades <b>208</b> and <b>210</b>. At step <b>460</b>, longitudinal axis <b>312</b> of pedicle screw removal tool <b>300</b> is positioned generally coplanar and parallel with longitudinal axis <b>226</b> of threaded section <b>202</b>. Longitudinal axis <b>312</b> of pedicle screw removal tool <b>300</b> is generally positioned offset from longitudinal axis <b>226</b> of threaded section <b>202</b> such that the axes are not axially aligned. At step <b>462</b>, end cap <b>216</b> is reengaged with body <b>204</b> to secure tip <b>308</b> to pedicle screw <b>200</b>. Optionally, end cap <b>216</b> remains disengaged from body <b>204</b>. In the event that end cap <b>216</b> is compromised and cannot be removed, tip <b>308</b> is inserted into channel <b>206</b> from the side and underneath end cap <b>216</b>. At step <b>464</b>, pedicle screw removal tool <b>300</b> is rotated in direction <b>228</b> around pedicle screw <b>200</b>, generally counter-clockwise, to unscrew pedicle screw <b>200</b> from the bone. Rotation of pedicle screw removal tool <b>300</b> can be accomplished by use of handle <b>306</b> or, if necessary, a torque producing tool such as a ratchet attached to head <b>310</b>. Motorized torque producing tools may also be employed. At step <b>466</b>, the trajectory of the tool may optionally be adjusted to a different angle by loosening the end cap, realigning the axis of the tool with respect to the screw and retightening the end cap.

Use of pedicle screw removal tool <b>300</b> eliminates the need to locate a matching removal tool for the pedicle screw regardless of whether or not the socket has been compromised. This procedure improves the speed and accuracy of pedicle screw removal as time is not wasted locating the proper sized tool, or fabricating custom tools. Further, safety is improved by reducing time required attending to unnecessary tissue damage and contamination.

Referring to <figref idref="DRAWINGS">FIG. <b>5</b></figref>, an alternate embodiment will be described. Pedicle screw removal tool <b>500</b> is a generally cylindrical shaft comprising lower section <b>502</b> integrally formed with and connected to neck <b>504</b>. Neck <b>504</b> is integrally formed with and connected to handle <b>106</b>. Neck <b>504</b> radially expands from lower section <b>502</b> to handle <b>506</b>. Tip <b>508</b> is integrally formed with and connected to lower section <b>502</b> opposite neck <b>504</b>. Head <b>510</b> is integrally formed with and connected to handle <b>506</b> opposite neck <b>504</b>. Lower section <b>502</b> is axially aligned with neck <b>504</b>. Neck <b>504</b> is axially aligned with handle <b>506</b>. Handle <b>506</b> is axially aligned with head <b>510</b>. Lower section <b>502</b>, neck <b>504</b>, handle <b>506</b>, and head <b>510</b> all share central longitudinal axis <b>512</b>. Handle <b>506</b> further includes opposing members <b>514</b> and <b>515</b>. Tip <b>508</b> is generally “L” shaped formed by prong <b>516</b>. Prong <b>516</b> extends from tip <b>508</b> generally perpendicular to lower section <b>502</b>. In a preferred embodiment, pedicle screw removal tool <b>500</b> is constructed of surgical grade steel.

The overall length of pedicle screw removal tool <b>500</b> can range from approximately eight to twelve inches depending on desired use. Prong <b>516</b> generally ranges from ⅛ to ½ inch in diameter. The length of prong <b>516</b> ranges from approximately ½ to one inch. Lower section <b>502</b> ranges in length from approximately three to five inches. Lower section <b>502</b> generally ranges from ⅛ to ½ inch in diameter. The length of neck <b>504</b> ranges from approximately one to two inches. Neck <b>504</b> is a generally frustoconical shape with an increasing diameter from a range of ⅛ to ½ inch in diameter at the connection of neck <b>504</b> to lower section <b>502</b> to a range of ½ inch to ¾ inch in diameter at the connection of neck <b>504</b> to handle <b>506</b>. Handle <b>506</b> ranges in length from approximately three to four inches. Handle <b>506</b> generally ranges from ½ to ¾ inch in diameter. Members <b>514</b> and <b>515</b> are generally cylindrical (however, other cross-sections are envisioned), are axially aligned, and extend from handle <b>506</b> generally perpendicular to handle <b>506</b>. Members <b>514</b> and <b>515</b> each range in length from approximately one and ½ to two inches. Members <b>514</b> and <b>515</b> generally range from ½ to ¾ inch in diameter. Head <b>510</b> ranges in length from approximately ½ to one inch. Head <b>510</b> has a generally square cross-section width a width that ranges from approximately ⅛ to ¾ of an inch. In alternate embodiments, head <b>510</b> may have other polygonal cross-sectional shapes suitable for attachment of a torque producing tool.

In use, in addition to the previous methods discussed, members <b>514</b> and <b>515</b> may be used to assist in the rotation of pedicle screw removal tool <b>500</b> in order to remove tuliped pedicle screws.

Referring to <figref idref="DRAWINGS">FIG. <b>6</b></figref>, an alternate embodiment will be described. Pedicle screw removal tool <b>600</b> is a generally tapered cylindrical shaft comprising an angled lower section <b>602</b> integrally formed with neck <b>604</b>. Neck <b>604</b> is integrally formed with handle <b>606</b>. Tip <b>608</b> is integrally formed with lower section <b>602</b> opposite neck <b>604</b>. Head <b>610</b> is integrally formed with handle <b>606</b> opposite neck <b>604</b>. Lower section <b>302</b> extends at angle <b>614</b> from neck <b>604</b>. Neck <b>604</b> is axially aligned with handle <b>606</b>. Handle <b>606</b> is axially aligned with head <b>610</b>. Neck <b>604</b>, handle <b>606</b>, and head <b>610</b> all share central longitudinal axis <b>612</b>. Tip <b>608</b> is generally “L” shaped formed by prong <b>616</b>. Prong <b>616</b> extends from tip <b>608</b> generally perpendicular to longitudinal axis <b>612</b>. Longitudinal axis <b>612</b> intersects prong <b>616</b>. In a preferred embodiment, pedicle screw removal tool <b>600</b> is constructed of surgical grade stainless steel.

The overall length of pedicle screw removal tool <b>600</b> can range from approximately eight to twelve inches depending on desired use. Prong <b>616</b> generally ranges from ⅛ to ½ inch in diameter. The length of prong <b>616</b> ranges from approximately ½ to one inch. Lower section <b>602</b> ranges in length from approximately three to five inches. Lower section <b>602</b> generally ranges from ⅛ to ½ inch in diameter. Angle <b>614</b> ranges from approximately 15° to 45°. The length of neck <b>604</b> ranges from approximately one to two inches. Neck <b>604</b> is a generally frustoconical shape with an increasing diameter from a range of ⅛ to ½ inch in diameter at the connection of neck <b>604</b> to lower section <b>602</b> to a range of ½ inch to ¾ inch in diameter at the connection of neck <b>604</b> to handle <b>606</b>. Handle <b>606</b> ranges in length from approximately three to four inches. Handle <b>606</b> generally ranges from ½ to ¾ inch in diameter. Head <b>610</b> ranges in length from approximately ½ to one inch. Head <b>610</b> has a generally square cross-section width a width that ranges from approximately ⅛ to ¾ of an inch. In alternate embodiments, head <b>610</b> may have other polygonal cross-sectional shapes suitable for attachment of a torque producing tool.

Referring to <figref idref="DRAWINGS">FIG. <b>7</b></figref>, an alternate embodiment will be described. Pedicle screw removal tool <b>700</b> is a generally tapered cylindrical shaft comprising lower section <b>702</b> integrally formed with and connected to neck <b>704</b>. Neck <b>704</b> is integrally formed with and connected to handle <b>706</b>. Tip <b>708</b> is integrally formed with and connected to lower section <b>702</b> opposite neck <b>704</b>. Head <b>710</b> is integrally formed with and connected to handle <b>706</b> opposite neck <b>704</b>. Lower section <b>702</b> is axially aligned with neck <b>704</b>. Neck <b>704</b> is axially aligned with handle <b>706</b>. Handle <b>706</b> is axially aligned with head <b>710</b>. Lower section <b>702</b>, neck <b>704</b>, handle <b>706</b>, and head <b>710</b> all share longitudinal axis <b>712</b>. Tip <b>708</b> is generally “T” shaped formed by prongs <b>714</b> and <b>715</b>. Prongs <b>714</b> and <b>715</b> are axially aligned and extend from tip <b>708</b> generally perpendicular to lower section <b>702</b>. The twin prongs of pedicle screw removal tool <b>700</b> are important in cases where access to the screw channel is obstructed from one side or the other. In these cases, either prong may be used in the channel to remove the screw. In a preferred embodiment, pedicle screw removal tool <b>700</b> is constructed of surgical grade stainless steel.

The overall length of pedicle screw removal tool <b>700</b> can range from approximately eight to twelve inches depending on intended use. Prong <b>714</b> and <b>715</b> generally range from ⅛ to ½ inch in diameter. The length of each prong <b>714</b> and <b>715</b> ranges from approximately ¼ to ½ inch. Lower section <b>702</b> ranges in length from approximately three to five inches. Lower section <b>702</b> generally ranges from ⅛ to ½ inch in diameter. The length of neck <b>704</b> ranges from approximately one to two inches. Neck <b>704</b> generally expands from a range of ⅛ to ½ inch in diameter at the connection of neck <b>704</b> to lower section <b>702</b> to a range of ½ inch to ¾ inch in diameter at the connection of neck <b>704</b> to handle <b>706</b>. Handle <b>706</b> ranges in length from approximately three to four inches. Handle <b>706</b> generally ranges from ½ to ¾ inch in diameter. Head <b>710</b> ranges in length from approximately ½ to 1 inch. Head <b>710</b> has a generally square cross-section width a width that ranges from approximately ½ to ¾ of an inch. In alternate embodiments, head <b>710</b> may have other polygonal cross-sectional shapes suitable for attachment of a torque producing tool.

Referring to <figref idref="DRAWINGS">FIG. <b>8</b></figref>, an alternate embodiment will be described. Pedicle screw removal tool <b>800</b> is a generally tapered cylindrical shaft comprising a offset lower section <b>802</b> integrally formed with neck <b>804</b>. Neck <b>804</b> is integrally formed with handle <b>806</b>. Tip <b>808</b> is integrally formed with lower section <b>802</b> opposite neck <b>804</b>. Head <b>810</b> is integrally formed with handle <b>806</b> opposite neck <b>804</b>. Neck <b>804</b> is axially aligned with handle <b>806</b>. Handle <b>806</b> is axially aligned with head <b>810</b>. Neck <b>804</b>, handle <b>806</b>, and head <b>810</b> all share central longitudinal axis <b>812</b>. Lower section <b>802</b> comprises segments <b>818</b> and <b>820</b>. Segment <b>818</b> is generally parallel with longitudinal axis <b>812</b> and connects segment <b>820</b> to tip <b>808</b>. Segment <b>820</b> extends generally perpendicular to longitudinal axis <b>812</b> from neck <b>804</b>. Prong <b>816</b> extends from segment <b>818</b> generally perpendicular to longitudinal axis <b>812</b>. Longitudinal axis <b>812</b> intersects prong <b>816</b>. In a preferred embodiment, pedicle screw removal tool <b>800</b> is constructed of surgical grade stainless steel.

The overall length of pedicle screw removal tool <b>800</b> can range from approximately eight to twelve inches depending on desired use. The length of prong <b>816</b> ranges from approximately ½ to 1 inch. Prong <b>816</b> generally ranges from ⅛ to ½ inch in diameter. Lower section <b>802</b> ranges in length from approximately three to five inches. Lower section <b>802</b> generally ranges from ⅛ to ½ inch in diameter. Segment <b>820</b> ranges in length from approximately ½ to 1 inch. Segment <b>820</b> generally ranges from ⅛ to ½ inch in diameter. The length of neck <b>804</b> ranges from approximately one to two inches. Neck <b>804</b> is a generally frustoconical shape with an increasing diameter from a range of ⅛ to ½ inch in diameter at the connection of neck <b>804</b> to lower section <b>802</b> to a range of ½ inch to ¾ inch in diameter at the connection of neck <b>804</b> to handle <b>806</b>. Handle <b>806</b> ranges in length from approximately three to four inches. Handle <b>806</b> generally ranges from ½ to ¾ inch in diameter. Head <b>810</b> ranges in length from approximately ½ to 1 inch. Head <b>810</b> has a generally square cross-section width a width that ranges from approximately ⅛ to ¾ of an inch. In alternate embodiments, head <b>810</b> may have other polygonal cross-sectional shapes suitable for attachment of a torque producing tool.

Referring to <figref idref="DRAWINGS">FIG. <b>9</b></figref>, an alternate embodiment will be described. Pedicle screw removal tool <b>900</b> is generally a cylindrical shaft comprising lower section <b>902</b> integrally formed with and connected to center section <b>909</b> and neck <b>904</b>. Tip <b>908</b> is integrally formed with and connected to lower section <b>902</b> opposite neck <b>904</b>. Lower section <b>902</b> is axially aligned with neck <b>904</b>. Neck <b>904</b> is generally of a larger diameter than lower section <b>902</b>. The diameter of the tool is reduced gradually within the handle along center section <b>909</b>, which is frustoconical in shape. Neck <b>904</b> is axially aligned with handle <b>906</b>. Handle <b>906</b> is axially aligned with head <b>910</b>. In a preferred embodiment, head <b>910</b> is a′/4 inch square cross section adapted to fit a ratchet drive. Annular indention <b>911</b> is positioned adjacent and distal to head <b>910</b>. In a preferred embodiment, annular indention <b>911</b> and head <b>910</b> are adapted to fit an AO connect handle or a T-handle as known in the art.

In a preferred embodiment, handle <b>906</b> is comprised of angular end stop <b>905</b> connected to convex center section <b>950</b> and angular end stop <b>907</b>. Handle <b>906</b>, in a preferred embodiment, is integrally formed of a nitrile rubber, a polyethylene plastic, or a Teflon® material, inductively welded to the tool to prevent movement of the handle with respect to center section <b>909</b>. Other medical grade pliable and flexible rubber or pliable plastic or polymeric materials can be used. Handle <b>906</b> is generally cylindrical and surrounds the tool having a common axis in a common central axis with the tool. Lower section <b>902</b>, neck <b>904</b>, handle <b>906</b> and head <b>910</b> all share longitudinal axis <b>912</b>. Tip <b>908</b> is generally L-shaped including prong <b>916</b>. Prong <b>916</b> extends from lower section <b>902</b> generally perpendicular to longitudinal axis <b>912</b>. Longitudinal axis <b>912</b> intersects the axis of prong <b>916</b> intersects axis <b>913</b> of prong <b>916</b>. In a preferred embodiment, pedicle screw removal tool <b>900</b> is constructed of rigid, unbendable surgical grade stainless steel, with dimensions similar to those previously described.

Pedicle screw removal tools <b>600</b>, <b>700</b>, <b>800</b> and <b>900</b> can each be used to remove any size tuliped pedicle screw.

In use, end cap <b>216</b> is removed. Rod <b>222</b> is removed. Tissue surrounding body <b>204</b> of the pedicle screw is removed. When using tool <b>600</b>, tip <b>608</b> is inserted into channel <b>206</b> such that prong <b>616</b> is adjacent blades <b>208</b> and <b>210</b>. When using tool <b>700</b>, tip <b>708</b> is inserted into channel <b>206</b> such that prongs <b>714</b> and <b>715</b> are adjacent blades <b>208</b> and <b>210</b>. When using pedicle screw removal tool <b>800</b>, tip <b>808</b> is inserted into channel <b>206</b> such that prong <b>816</b> is adjacent blades <b>208</b> and <b>210</b>. In the case of tools <b>600</b>, <b>700</b> and <b>800</b>, longitudinal axis <b>612</b>, <b>712</b>, or <b>812</b> is positioned generally coaxial with longitudinal axis <b>226</b> of threaded section <b>202</b>. The pedicle screw removal tool is rotated, generally counter-clockwise, to dislodge pedicle screw <b>200</b> from its attachment to the bone. Rotation of the pedicle screw removal tool can be accomplished by hand using the handle or, if necessary, a torque producing tool such as a wrench or ratchet can be attached to the head.

It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this disclosure is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present disclosure as defined by the appended claims.